The present invention relates to formation of conductor junctions in primary conductors of an electrical distribution system of 15,000 volts (15 KV) or higher using standard compression terminals for linking the conductors. In particular, the invention relates to re-insulation of the formed junctions.
Primary conductors provide the main power supply in urban electrical distribution systems wherein public utility crews pull the primary conductors through underground duct systems in lengths sufficient only to reach between vaults spaced a block apart in downtown business districts with the cable being spliced in each vault. In many vaults, a primary service must be taken off by means of a three conductor junction to supply power to a customer's building adjacent the vault.
In most cases, the three conductors are not the same size and therefore a special Y-shaped connector has to be made. Y-shaped connectors in both copper and aluminum have been used for many years, however, the available quantity of such connectors is always small, and the customer's requirements must be known well in advance to allow sufficient time to make-to-order the required Y-shaped connectors.
Primary conductors in general, are supplied having one or the other of two types of insulation, either solid dielectric (e.g., high density polyethylene) or "paper and lead" in which the cable intersticies are filled with oil. When the two types of cables are to be joined, as is often the case, the migration of oil from the "paper and lead" cable into the solid dielectric cable must be prevented. For a two conductor splice of same size, different type (i.e., one oil filled, one not) oil stop connectors are available, for example Burndy Corporation type YSP-T "oil stop" HYSPLICE connectors.
Improvement is needed in the art of primary conductor splices taking into account the different insulation types and sizes of conductors particularly in cases where three or more conductors form a junction. The use of standard connector terminals has always been a possibility; however, there has never been found a simple, expedient way to apply the insulating materials over that area of the junction where the terminal pads of standard connectors are bolted together. This invention solves that problem.